An OTFS-DFRC Waveform Design Method Based on Phase Perturbation

Orthogonal time frequency space (OTFS) is a new communication waveform modulation method. It was first proposed in the field of communication to counter the doubly dispersive channel under high Doppler, but it also has great potential in the field of radar. This letter proposes an OTFS modulated waveform design method with dual functions of radar and communication based on phase perturbation, mainly studies the radar performance of OTFS waveform, derives the expression of the ambiguity function of OTFS waveform, focuses on the range-velocity two-dimensional sidelobe, and optimizes the peak sidelobe level of ambiguity function by adding phase perturbation to each communication symbol. Simulation results show that this algorithm can effectively reduce the peak sidelobe level of OTFS, and it only brings slight symbol error rate loss. The tradeoff between radar and communication can be achieved by adjusting the upper bound of the perturbation.